85huntsman

I saw in the manual that the short bed pickup has a 13.7 gallon tank and the long beds were 17. From our travels, the tank felt way more like 13.7 than 17. Would a 17 gallon tank fit? I've looked online for a replacement tank, but all I have found are 17 gallon tanks.

My fuel tank is leaking, and we want to replace it. Does anyone know if the tank for an 85 4runner will work or if a different tank was used on these?